Growth and metal uptake of energy sugarcane (Saccharum spp.) in different metal mine tailings with soil amendments.

A pot experiment was conducted to investigate the feasibility of growing energy sugarcane (Saccharum spp.) in three different metal mine tailings (Cu, Sn and Pb/Zn tailings) amended with uncontaminated soil at different mixing ratios. The results indicated that sugarcane was highly tolerant to tailing environments. Amendments of 20% soil to Sn tailings and 30% soil to Cu tailings could increase the biomass of cane-stem for use as the raw material for bioethanol production. Heavy metals were mostly retained in roots, which indicated that sugarcane was useful for the stabilization of the tailings. Bagasse and juice, as the most valuable parts to produce bioethanol, only accounted for 0.6%-3% and 0.6%-7% of the total metal content. Our study supported the potential use of sugarcane for tailing phytostabilization and bioenergy production.